1.
( formal ) to see sth take place :
He has been witness to a terrible murder.
2.
to show that sth is true; to provide evidence for sth :
His good health is a witness to the success of the treatment.
1.
( formal ) to see sth take place :
He has been witness to a terrible murder.
2.
to show that sth is true; to provide evidence for sth :
His good health is a witness to the success of the treatment.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005